This chapter is from the book

This chapter is from the book

Although, apparently, Photoshop layers and the Shapes tools have nothing in
common, when you get to real-world assignments, you'll find yourself
continually using first one feature and then the other.

Why? Adobe has made creating shapes very simple, somewhat like opening a
template of a design. To make image creation even easier, Adobe invented
something called vector masks. Vector masks are pre-designed
shapesthey act as tiny portals to layers underneath the layer upon which a
vector mask resides, or they can appear as shapes against the background. You
can change their color and add all sorts of wonderful effects to them.
But...vector masksshapeswork only on layers, and that's
why these two features are grouped into a single chapter.

Examining the Flexibility of Layers

Layers have been a Photoshop feature since version 3.0 (shortly after
electricity was discovered). In passing years, Adobe has made the layers feature
so powerful that today it almost overshadows Photoshop's most-used feature:
the shipload of different ways you can select image areas.

In the sections that follow, you become familiar with Layer modes, layer
locking, layer linking, clipping groups, clipping paths, layer sets, layer
ordering, layer deleting, and Layer effects. Is learning all this stuff
necessary? Yes, most certainly so; once you make layers a part of your Photoshop
knowledge, you will work at least twice as fast as the next (uneducated) guy or
gal.

First, we felt you'd benefit most from a potpourri-style tutorial, where
you learn exactly what you need to know about a number of different layer
tools and features. You'll see how efficiently you can work to perform
complicated image editing.

Introducing the "Pocket Contents" Image

If someone were to ask you to empty the contents of your pockets on a
table:

You're probably being booked for a crime, and

You'll notice that from an artistic standpoint, the composition
formed by dumping your pockets is dimensional. Everything is not neatly ordered
and distributed. This could be considered to constitute layers of things.
Your keys might be above some folded money, and the folded money partially hides
some pocket change.

The point here is that realistic image composition inherently has a depth of
field; things go in front of and behind other elements. This is where Photoshop
layers come in handy. They can help imitate real-world compositions.

Now, imagine you're Jim Carreythe only comedian whose adopted
planet is Earth and you're asked to dump out your pockets on a table.
The contents would probably be like the contents of the Pocket.psd image
you'll work with in a moment.

The image looks like any other table top scene, except this scene was
rendered in a modeling program, and everything is on different layers. FYI,
shadows are attached to everything using the glow and shadow technique you will
become familiar with in Chapter 5, "Working with Channels and Paths."
Let's start off slow and easy as you learn how to manipulate the ordering
of layers.

Investigating Layer Order

Open the Pocket.psd image from the Examples/Chap04 folder on the
Companion CD, and save it to your hard disk using the same name and file type.
This image is 600 by 800 pixels, with a resolution of 72 pixels per inch; zoom
in or out if necessary to see all the contents of the image window.

Press F7 to display the Layers/Channels/Paths/And So On grouped palette.
Press V to switch tools to the Move tool.

And remember this shortcut: When the toolbox is partially hidden or
closed, pressing V selects the Move tool directly, saving you the trouble of
looking through the toolbox for the tool you need.

Right-click (Macintosh: hold Ctrl and click) over the 15ball in the
image. As you can see in Figure 4.1, the context menu offers two layers
presently underneath your cursor, called the 15ball and the Background. Click
the 15ball choice, and you will see that the 15ball layer on the Layers palette
is highlighted. You've made the 15ball layer the current editing
layer.

Figure 4.1 Move directly to a layer you want to edit by right-clicking
(Macintosh: hold Ctrl and click) the area you want to edit.

WARNING

Avoid Auto Select Accidents When the Move tool is selected, the
Options bar offers a checkbox for Auto Select Layer. We don't recommend
using this option if you're a novice to Photoshopor even an
intermediate user. When the option is checked, if you click anywhere in the
image with the Move tool, you immediately move to the layer that was underneath
your cursor. Can you see how this option can be both confusing and hazardous to
your work?

You can take a safer route to select a layer quickly when the Move tool is
active, however. Simply Ctrl()+click to move to a specific
object on that layer. This enables you to change layers when it's
convenient and avoids the accidental layer jumping you might do if Auto Select
were enabled.

Drag the 15ball downward so that it is between the dart and the ice
cream. Let's say we want the 15ball to play a more predominant role in the
composition. No problem. On the Layers palette, drag the layer title for the
15ball up between the Soft Ice Cream layer and the Dart layer, as shown
in Figure 4.2. This puts the 15ball layer between the dart and ice cream layers.
And like me, you might not hit the "sweet spot" on the palette on your
first try. If you release the layer title on top of a layer, it then
resides directly beneath the layer upon which you dropped it. This
technique might be worth a few practice stokes on your own.

Figure 4.2 Move the order in which layers are organized to place an object
in front of another.

NOTE

Moving Through Layers, the Fast Way We acknowledge that we are
cramming your head with stuff here. If you feel you have the memory (the
carbon-based, organic kind), you can learn a keyboard method to change a
selected layer's position in the stack of layers. Press Ctrl()+] (right bracket) to move the chosen layer up by one layer. As you
might expect, to demote a layer, press Ctrl()+[ (left
bracket), one stroke per layer downward in the stack.

Photoshop uses the same ordering commands for layers as Illustrator and
PageMaker do for objects.

Play around with the position of the 15ball as much as you like.
There's no exam at the end of this chapter. It's sort of fun to see
how the shadow and pool ball cover different layer items. Keep the image and
Photoshop open.

A Photoshop layer has more than one property. A layer is not only a container
in a stack of other layersit also can be changed with respect to opacity
and how the layer's contents blend with layers underneath it. Come explore
layer properties in the following section.

Changing the Appearance of a Layer

If you change a property of a layer in Photoshop, you also are likely to
change the same property of whatever is on that layer. There are eight things
that you can do to a layer, without mixing a layer with an additional,
modifying layer (covered later in this chapter). The sections that follow
introduce you to these different properties.

Opacity

When you're using a selection tool or the Move tool, you can change the
opacity of a layer and its contents by doing the following:

Planting your cursor in the Opacity field and typing. If you type a
single digit, this represents 10 times the opacity applied. In other words, type
5, and 50% will appear in the number field. A zero (0) represents 100% opacity.
Typing two numbers, one right after the otherno pausingwill enter
these two numbers in the number entry field. Typing 5 and then 7, for example,
will make the opacity 57%.

Typing a number value when your cursor is anywhere in the
interface. This, too, affects the opacity of the current layer. This may not be
your preferred method because it might be unsettling to type a number while
working in a channel and inadvertently change the opacity of a layer.

Click the Soft Ice Cream layer title, click and hold on the
palette's opacity flyout button, and then drag the opacity down to 57%, as
shown in Figure 4.3. This is the direct, hands-on opacity determining
method.

The Modes Drop-Down List

In Photoshop, you can paint using a certain mode you choose from the Options
bar, and you also can put an entire layer's contents into most of the same
modes. Photoshop has 22 modes, which means that you have 22 different ways to
blend a layer into the underlying layers.

After using layer modes in several versions of Photoshop, I have discovered
that there are four modes you'll use regularly: Normal, Multiply, Screen,
and Overlay. You also will experiment on your own and find the perfect blending
mode for your own images, but let's cover the "basic four" here
and now:

Normal. Normal is the default mode, and the blend between the
target layer and the layer(s) underneath is simple math. For example, if a layer
is 50% opaque and the image underneath is 100% opaque, the resulting image at
any point will be a color combination of 50% layer and 50% background image. Try
making a bright blue background and a bright red layer, and then tuning the
layer down to 50% opacity. The resulting color, in Normal mode, is a deep
purple.

Multiply. This is a terrific blending mode for working shadows
into images. Multiply mode replaces colors with a combination of layer colors
that is subtractive in regions that are less than 50% in brightness. Huh? Okay,
think of staining something light in color with a blue marker pen. Only the
target area gets darker. Now, imagine a white marker. Writing across the surface
of something with the white marker causes no difference in the surface's
colordue to the fact that no subtractive color process is going on with a
light color and a light target in Multiply mode.

Screen. If Multiply mode is like staining something, Screen mode
is like bleaching something; it's the exact opposite effect. In Screen
mode, lighter colors become more intense, while deeper colors do not change (and
again, 50% brightness is the break point for what Photoshop considers light and
dark). Try out Screen mode in the Pocket image, on the partially visible Ice
Cream Cone layer. As you can see in Figure 4.4 (and much better on your
own monitor), Screen mode really brings out the whites of the vanilla ice cream,
and the deeper shadow areas on the cone seem to vanish.

Figure 4.4 Screen mode is useful if you have a layer with light colors
that you want to separate off a dimly lit background.

Overlay. This mode produces an effect somewhat similar to placing
a colored gel over an image. Overlay mode blends the image color with the
Overlay color. Highlights and shadows do not change in brightness, but colors
with a brightness between shadows and highlights are screened if they are over
50% in brightness. Additionally, colors are multiplied if the image's
original color is less than 50% bright. You'll see a good example of this
color mode in Chapter 5 with the ball and the pattern on the ball.

There are two more ways in which you can change the appearance of a layer,
and both controls are located to the left of a layer title on the Layers
palette.

Fill

The Fill slider on the Layers palette enables you to achieve two different
kinds of opacity on a single layer. The Opacity setting controls the
transparency of the layer; a setting of 100% means that the layer beneath the
current layer cannot be seen through the objects on the selected later. A
setting of 50%, however, fades the layer to allow 50% transparency so that
objects on other layers will be visible through the current one. Fill (which is
short for Fill Opacity) actually enables you to fade out the pixels or shapes
you draw on the selected layer. It is used primarily when you have applied a
layer effect, such as Emboss or Drop Shadow. When you reduce the Fill value, the
pixels on the layer become increasingly transparent, but the layer effect
remains.

Give the Fill control by trying this: Using the Pocket image (we're
going to trash this image through the course of the chapter, so don't worry
about messing it up), click the Soft Ice Cream layer, and with Opacity at 100%,
drag the Fill slider down to about 50%. Ooooh, ghostly ice cream!

Now let's restore the Fill setting to 100% for this layer. We have more
to do with this image, and you can always mess with the Fill feature (it's
new to Photoshop 7, by the way) on other layered images later.

Visibility and Edibility Icons

The Layers palette shows two columns to the left of any layer. These columns
contain icons that let you know which layers are visible and available for
editing. The leftmost one concerns us here. Be patientwe'll get to
the second one soon.

The visibility icon, in the leftmost column, is pretty self-explanatory.
If there's an eye in the box, this means you can see the contents of the
layer. If you click the eye, it disappears, and so does the visibility (and
editing) of the layer's content.

Also, the Lock feature (new to version 7) has an option for painting.
If you click the brush icon, you'll get one of those international "do
not" symbols if you try to paint this layer.

TIP

Hide It and You Won't (Accidentally) Edit It Photoshop users have
been leveraging the power of the visibility icon for years by turning the
visibility of a layer off so that no accidental editing can happen to the
layer.

The column to the left of the visibility column is called the Layer Link
Mode column, and the appearance (or absence) of a link icon tells you whether a
layer is linked. But you may actually see a few different icons in this column,
depending on which state the layer is in. There are four possible states into
which you can toss a layer: the target layer state, the Layer Mask state, the
Layer Link mode, and the lock list. In the target layer state, the icon
resembles a paintbrush; in layer mask, it looks like a gray rectangle with a
white circle; and in layer link mode, the icon appears to be a chain. When you
choose one of the lock list items, a small padlock appears to right of the layer
name.

Target Layer State

You can paint on only one layer at a time in Photoshop, and you choose that
layer by either keyboarding your way to a layer or by clicking its title on the
Layers palette. When the layer is highlighted, it is called the target layer. A
paintbrush icon in this column's box indicates that this layer is the
target (current editing) layer. The title bar on the image also lists the
current layer.

Layer Mask State

Later in this chapter, you edit the Pocket composition, using the layer mask.
The quickest way to put a layer into the Layer Mask state is to choose the
layer, and then click the icon that is second from the left on the bottom of the
Layers palette. When a layer is in Layer Mask mode, you see the same icon in the
box in the second column next to the Layer title.

What's this state do? Layer masks enable you to control the parts
of the image you want to be able to edit, hide, or reveal. But not to worry!
We're getting ahead of ourselves here, and you will play with the
Layer Mask state later in this chapter!

Layer Link Mode

You'll be doing a step-by-step procedure with the Layer Link state later
in this chapter, too. If you click in the second column box when the Paintbrush
icon (target layer) isn't there, this layer turns into a linked
layer, and a tiny chain appears in the column box. This layer is linked to the
target layer, and if you use the Move tool to move the target layer's
contents, the linked layer's contents moves correspondingly. This is a
terrific feature when you have two objects aligned on different layers and you
want to move them both, but you do not want to merge the layers. A click in a
box that contains the link icon unlinks the layers.

We've saved the least critical three controls for layers for last.
Don't worry if you find you are not using them daily in your work.

The Lock List

You've had a taste of this list with the Lock Image Pixels (that teeny
brush icon). This horizontal list above the top layer title is probably used
most often by intermediate to advanced users, primarily because these users are
the ones who create intermediate to advanced problems in an image, and
locking features are art-savers.

We have no tutorial to show you how the Lock choices work, so you might want
to open a new image, and add a layer to it now. To do this, click the folded
page icon directly to the left of the trash icon on the bottom of the Layers
palette. Then use the Paintbrush tool to paint something, any color, on the
layer.

The default setting for the layer Lock feature is Lock nothing. This means
that no part of the layer is protected against accidental editing. You
can paint over the first strokes you've made in the image window, and you
also can paint over empty areas of the layer.

When you're ready to try out one of the Lock options, you can choose
from Lock transparent pixels, Lock image pixels, Lock position, or Lock all. The
paragraphs that follow explain each of these choices a bit more.

Set the Lock feature by clicking Lock transparent pixels, the first icon next
to the word "Lock" (see item 1 in Figure 4.5). Enabling this feature
locks the current opacity of the layer, no matter what the current setting might
be. Any areas on that layer that have even 1% opacity (and it's doubtful
any of us can see a 1% opaque area) cannot become more opaque, regardless of
what tool you use to paint.

Figure 4.5 The Lock feature can disable painting over areas, prevent
moving areas on a layer, and completely prevent editing on the target
layer.

The next icon, Lock image pixels, shown as item 2 in Figure 4.5, keeps you
from painting on the layer. Item 3, Lock position, stands for "no moving
stuff, bud." With this icon selected, you cannot use the Move tool to
accidentally or intentionally move any non-transparent areas on a target layer.
Finally, item 4, Lock all, stands for "you cannot do anything to this
layer; it is locked against everything."

You'll definitely use more options in your first months with Photoshop,
but it's nice to see some of the most common ones and know what they do.
Let's get back to our Pocket masterpiece, and explore more layer
features.